1. Field of the Invention
The present invention relates to a video slot machine that is installed in casinos or the like.
2. Background Information
One type of video slot machine will display a plurality of reel images on a monitor. Each reel image comprises at least two types of symbols that are arranged in a predetermined order, and the symbols will be changed and displayed in response to the rotation of the reels on the monitor. A determination unit of the video slot machine will generate a start signal and determine the symbols to be stopped and displayed on the monitor if it receives credit in response to a BET operation with an operation unit. In addition, the determination unit will successively switch the plurality of symbols displayed on the monitor, and stop the changing display of the reel images in order to display the symbols determined by the determination unit. Furthermore, in the event that the determination unit has determined that a predetermined payout prize from amongst a plurality of predetermined prizes has been won, credit will be paid out in an amount that corresponds to the predetermined payout prize. This type of video slot machine is similar to those disclosed in U.S. Pat. No. 6,641,477 and U.S. Pat. No. 6,731,313.
Generally, depending on the type thereof, a video slot machine will pay a large dividend at a low prize winning ratio, or will pay a small dividend at a high prize winning ratio. These features primarily depend on the symbol arrangement on the reel images, such as whether or not there are a large number of high dividend symbols on the reel images, or whether or not the positions of the high dividend symbols on the reel images are variable or fixed. Most conventional video slot machines are configured such that the reel images cannot be changed. Accordingly, it has been difficult to provide a video slot machine having both of these contradictory features.
In contrast, the video slot machines disclosed in U.S. Pat. No. 6,641,477 and U.S. Pat. No. 6,731,313 have a configuration that will allow a player to change some of the symbols on the reel images. In this type of video slot machine, only some of the symbols on the reel images can be changed by a player. Consequently, a player cannot make significant changes to the original features of this type of video slot machine. Thus, the aforementioned problem has yet to be solved.
In addition, the video slot machines disclosed in U.S. Pat. No. 6,641,477 and U.S. Pat. No. 6,731,313 require the player to change the symbols on the reel images. Typically, regular players, such as those who play video slot games for a long period of time or many times, prefer to play games that require as few operations as possible. Accordingly, regular players find video slot machines that require an operation from a player each time the symbols on the reel images are to be changed annoying, and this will cause game performance to decline.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved video slot machine that can execute a video slot game having at least two features that contradict each other, depending on the symbol arrangement, but will not annoy a player. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.